Abstract

The economy of the Commonwealth of Dominica is primarily agrarian based with
banana production as one of the key export commodities, notwithstanding its preferential loss
in the European Union market. However, banana productivity like most other crops has been
severely impacted by a general low native soil nutrient status coupled with low application
rates of phosphate (P) fertilizers in particular. The latter can be partly attributed to the low
purchasing power on the international market as is evident in the long term trends of increaseprices for nitrogenous and phosphate fertilizers.
The volcanic soils of the Commonwealth of Dominica were first studied in a relatively detailed way in 1967 with these soils showing high phosphate retention capacities. As a consequence, although P application is an integral part of profitable agricultural systems, improving soil fertility and plant nutrient management is a complex challenge. This challenge is amplified by the fact that a high ability to adsorb P is one of the characteristics of volcanic soils making P sparingly available for plant uptake. Hence although the world’s high reserves of phosphate ores are declining the demand for P fertilizers in the humid tropics are constantly increasing. If not managed properly, increase and continued input of P fertilizers and manure P may eventually lead to environmental rather than agronomic concerns.
This research examines the influence of soil properties from some major agricultural soils in the Commonwealth of Dominica in order to obtain an improved comprehension of soil fertility limitations with the goal of developing nutrient management and farm developmental strategies geared towards increased crop production and overall farm productivity. In this regard special attention is given to the use of pyroligenous acid as a low molecular weight organic acid (LMWOA) in catalysing the dissolution of secondary P minerals. Hence the aim is to understand how native P stocks as well as applied fertilizer can potentially become more plant available thus reducing P fertilizer applications to a required minimum.